Best Includes Source SDK Games on Steam

Name Release Date Current Players All-Time Peak Rating
Garry's Mod Garry's Mod 29 Nov, 2006 19 728 38 330 96.04
Left 4 Dead 2 Left 4 Dead 2 16 Nov, 2009 19 636 56 655 96.74
Counter-Strike: Source Counter-Strike: Source 1 Nov, 2004 8 736 14 784 95.07
No More Room in Hell No More Room in Hell 31 Oct, 2013 1 283 1 283 88.55
Half-Life 2 Half-Life 2 16 Nov, 2004 734 3 630 96.38
Portal Portal 10 Oct, 2007 727 2 092 97.17
Black Mesa Black Mesa 6 Mar, 2020 554 1 968 93.94
Left 4 Dead Left 4 Dead 17 Nov, 2008 380 1 651 94.62
Day of Defeat: Source Day of Defeat: Source 12 Jul, 2010 347 677 89.61
Alien Swarm: Reactive Drop Alien Swarm: Reactive Drop 20 Apr, 2017 336 664 92.74
Pool Nation FX Lite Pool Nation FX Lite 7 Dec, 2015 214 308 70.09
Half-Life 2: Episode Two Half-Life 2: Episode Two 10 Oct, 2007 168 530 95.16
Half-Life 2: Deathmatch Half-Life 2: Deathmatch 1 Nov, 2004 144 274 88.47
Astro Colony Astro Colony 7 Nov, 2022 120 742 79.31
Half-Life 2: Episode One Half-Life 2: Episode One 1 Jun, 2006 111 517 93.74
Fistful of Frags Fistful of Frags 9 May, 2014 88 206 89.63
Empires Mod Empires Mod 28 Jul, 2008 39 57 81.96
Selaco Selaco 30 May, 2024 39 1 104 89.75
Zombie Panic! Source Zombie Panic! Source 3 Oct, 2008 37 74 82.22
Day of Infamy Day of Infamy 23 Mar, 2017 23 63 81.03
Battle Grounds III Battle Grounds III 30 Jun, 2019 13 162 82.86
Pirates, Vikings, and Knights II Pirates, Vikings, and Knights II 12 Feb, 2010 13 65 84.92
Hidden Through Time 2: Discovery Hidden Through Time 2: Discovery To be announced 9 44 77.65
BrainBread 2 BrainBread 2 9 Mar, 2022 8 25 71.54
Absorber Absorber 9 Jul, 2023 6 70 71.15
Kreedz Climbing Kreedz Climbing 15 Jun, 2017 6 10 78.13
Sunrise: survival Sunrise: survival 3 Aug, 2017 5 19 49.41
Double Action: Boogaloo Double Action: Boogaloo 23 Oct, 2014 5 27 90.37
Rise of the Triad Rise of the Triad 31 Jul, 2013 4 23 64.53
Kingdom of Atham: Crown of the Champions Kingdom of Atham: Crown of the Champions 12 Jan, 2024 1 26 73.34
PLAY WITH ME Demo PLAY WITH ME Demo 17 Jan, 2018 0 0
Portal with RTX Portal with RTX 8 Dec, 2022 0 0
Halloween Content Pack Halloween Content Pack 25 Oct, 2016 0 0
Fortress Forever Fortress Forever 27 Mar, 2015 0 0 84.30
Requiem Of Science Requiem Of Science 7 Jan, 2022 0 0
Attack on Titan - Weapon - Christmas Attack on Titan - Weapon - Christmas 22 Nov, 2016 0 0 0.00
Kalahari’s End Kalahari’s End Coming soon 0 0
Obsidian Conflict Obsidian Conflict Coming soon 0 0
PACT - Process Affinity Control Tool PACT - Process Affinity Control Tool 31 Jan, 2021 0 1 50.00
Attack on Titan - Episode 2 Attack on Titan - Episode 2 27 Sep, 2016 0 0 59.60
Stryke Stryke To be announced 0 0
???? Human Rocket Person ???? Human Rocket Person 14 Nov, 2018 0 0 77.59
STATIK STATIK Coming soon 0 0
Attack on Titan - Mikasa Costume - Summer Festival Attack on Titan - Mikasa Costume - Summer Festival 20 Dec, 2016 0 0 0.00
Resoraki Demo Resoraki Demo 13 Apr, 2023 0 0
Forza Horizon 4: Hot Wheels™ Legends Car Pack Forza Horizon 4: Hot Wheels™ Legends Car Pack 9 Mar, 2021 0 0
FIREFIGHT RELOADED - Beta Versions DLC FIREFIGHT RELOADED - Beta Versions DLC 15 May, 2020 0 0
Twisted Jam Twisted Jam Q2 2025 0 0
Pool Nation FX - Unlock Objects Pool Nation FX - Unlock Objects 7 Oct, 2015 0 0 0.00
Shop Tycoon Demo Shop Tycoon Demo 10 Nov, 2021 0 0
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